Grate



June 9, 1925.

C. P. CALDWELL GRATE Filed March 10, 1921 gwue/wlio 'o N CharZ cf]? Caldwell,

LL HLL LL LLHL Patented June 9, 1925.

tantra UNITED A TE S. T EN T 0 F F! GE.

eHeBLEsr. nation-ELL. or KANSAS C T MISSQUBI- snare.

Application filodMarph 10, 1921. Serialln. 451,272.

To all a/rlzomjt may concern Be it known that I, CHARLES P. CALDWELL, a citizen of the United States, residing at Kansas City, in the county of. Jackson and State of Missouri, have invented certain new and useful Improvements in Grates, of which the following is a specification.

My invention relates to improvements in grates for use in domestic furnaces, station ary power plant furnaces, locomotive furnaces, or in fact, practically, any type of furnace, and an important feature of the invention resides in the provision of means for introducing air into the furnace at different elevations to suit different conditions of the fire, to the end that more perfeet combustion may be had than heretofore.

Other features will hereinafter appear, and in order that the invention may be fully understood, reference will now be had to the accompanying drawing, in which:

Fig. 1 is a fragmentary plan view of a portion of a grate embodying the invention...

' Fig. 2 is a cross section on line IIII of Fig. 1.

Fig. 3 is an enlarged vertical section of a tubular element constituting an important feature of the invention.

Fig. .t is afront elevation of a pawl and ratchet employed in carrying out the invention.

Fig. 5 is a detail perspective view of one form of tubular element.

Fig. 6 is a detail perspective view of another form of tubular element.

Referring now in detail to the various parts, ,A designates a part of the furnace walls in which the grate is installed. In the present instance said grate consists of two rockable sections 2 and an intermediate dead plate 1 which latter extends the full length of the former. The dead plate at has pockets 6 with openings 8 for the passage of tubular elements 10, which are freely adjustable in said pockets 6. The upper and lower sides of the pockets 6 constitute guides for the tubular elements 10 and also serve to retain suitable packing material 12 around said elements 10 to prevent the passage of air through the openings 8.

Each tubular element 10 is rectangular in cross section and has an inlet port 12 at its lower end and one or more outlet ports 14 at its upper portion. The top of the tubular element 10 slopes as indicated at- 16 to prevent the lodgment of fuel thereon and its lower end has a rack 18 for engagement with a pinion 20.

The pinions 20 are fixedly mounted upon a shaft 22 extending beneath the dead plate 4: and suitably journaled in the furnace. The outer end of the shaft 22 is of angular formation to receive a crank 24 whereby said shaft 22 may be rotated to effect vertical adjustment of the tubular elements 10 through the intermediacy of the pinions 20 and the racks 18.

The shaft 22 is provided near its outer end with a fixedly mounted ratchet wheel 26, which is normally engaged by a pawl 28 to prevent said shaft 22 from being rotated backwardly by the weight of the tubular elements 10.

In practice, when a fire is first started on the grate the tubular elements 10 are adjusted downwardly to bring the outlet ports 14 below the upper walls of the pockets 6, as I find that it retards combustion to admit air through said tubular elements 10 to the top of the fire when starting the same. As the fire gets under way the tubular elements are adjusted upwardly for the purposeof discharging the air through the ports letat an elevation relative to the upper portion of the fire to obtain the best results. As the oxygen in the air combines with the hot gases thrown off by the distillation of the fuel a combustible mixture is formed which consumes the smoke and gases and results in a saving of fuel.

By mounting the tubular elements 10 in the dead plate 4, said tubular elements are protected from being burned out as there will belittle or no fire on said dead plate due to insullicient air to support combustion. However, should one or more of the tubular elements 10 burn out they can be replaced at small cost.

The tubular element 1O disclosed by Fig. 6, is circular in cross section instead of rectangular like the tubular elements 10, and is well adapted for grates of small furnaces such as are used for heating dwellings. In such furnaces one tubular element 10 will generally sutlice and instead of being mounted in a long dead plate 4- as shown by Figs. 1 and 2, is preferably mounted in a circular dead plate 4? around which the open portion of the grate (not shown) can be suitably arranged.

.From the foregoing description it will be understood that I have produced means for the economical consumption of fuel and the elimination of smoke, and While I have shown tWo forms of the invention, I re serve the right to make such other forms as properly fall Within the spirit and scope of the claim.

Having thus described my invention, What I claim and desire to secure by Letters Patent, is:

In a furnace grate, a stationary dead plate extending the length of the grate and having a plurality of vertical openings with surrounding poekets, packing in said pockets,

tubular elements having air ports and extending through said openings and having; smooth parallel sides snugly fitting Within the packing, racks depending from said tubular elements, pinions internieshing with said racks to adjust the same vertically, a shaft upon which said pinions are fixed, and means for rotating said shaft.

In testimony whereof I affix my'signature, in the presence of two Witnesses.

CHARLES P. CALD'WELL. Vitnesses:

I*. G. Frsorrnu, L. J. Fisorrnm. 

